#include <wchar.h>

       size_t wcsnrtombs(char *dest, const wchar_t **src, size_t nwc,
                         size_t len, mbstate_t *ps);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

           Since glibc 2.10:
               _XOPEN_SOURCE >= 700 || _POSIX_C_SOURCE >= 200809L
           Before glibc 2.10:

       The  wcsnrtombs()  function  is  like the wcsrtombs(3) function, except
       that the number of wide characters to be converted, starting  at  *src,
       is limited to nwc.

       If  dest  is  not a NULL pointer, the wcsnrtombs() function converts at
       most nwc wide characters from  the  wide-character  string  *src  to  a
       multibyte  string  starting  at dest.  At most len bytes are written to
       dest.  The shift state *ps is updated.  The conversion  is  effectively
       performed  by  repeatedly  calling  wcrtomb(dest, *src, ps), as long as
       this call succeeds, and then incrementing dest by the number  of  bytes
       written and *src by one.  The conversion can stop for three reasons:

       1. A wide character has been encountered that can not be represented as
          a multibyte sequence (according to the  current  locale).   In  this
          case   *src   is  left  pointing  to  the  invalid  wide  character,
          (size_t) -1 is returned, and errno is set to EILSEQ.

       2. nwc wide characters have been converted without encountering a  null
          wide  character (L'\0'), or the length limit forces a stop.  In this
          case *src is left pointing to the next wide  character  to  be  con-
          verted, and the number of bytes written to dest is returned.

       3. The  wide-character  string has been completely converted, including
          the terminating null wide character (which has the  side  effect  of
          bringing  back  *ps to the initial state).  In this case *src is set
          to NULL, and the number of bytes written to dest, excluding the ter-
          minating null byte ('\0'), is returned.

       If  dest is NULL, len is ignored, and the conversion proceeds as above,
       except that the converted bytes are not written out to memory, and that
       no destination length limit exists.

       In both of the above cases, if ps is a NULL pointer, a static anonymous
       state known only to the wcsnrtombs() function is used instead.

       The programmer must ensure that there is room for at least len bytes at

       Passing NULL as ps is not multithread safe.

       iconv(3), wcsrtombs(3)

       This  page  is  part of release 3.54 of the Linux man-pages project.  A
       description of the project, and information about reporting  bugs,  can
       be found at http://www.kernel.org/doc/man-pages/.

GNU                               2011-10-16                     WCSNRTOMBS(3)
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